Eosinophilic Angiocentric Fibrosis of Sinonasal Region: A Rare & Under Reported Entity

Eosinophilic angiocentric fibrosis is a rare pathology of the sinonasal tract and the upper respiratory system characterised by fibrosis with poorly understood pathogenesis. A 47-year-old male presented with a swelling over the dorsum of the nose. The possibility of fungal granuloma was being suggested on Magnetic Resonance Imaging (MRI). Histopathology showed thick collagen bundles whorling around vessels giving an onion skin appearance with focal area of vasculitis. An inflammatory reaction rich in eosinophils along with a fibrotic stroma was seen which was highly characteristic of eosinophilic angiocentric fibrosis. Clinically & microscopically it mimics Granuloma faciale, Wegener's Granulomatosis, Churg-Strauss Syndrome, Kimura's disease and few other granulomatous conditions thus making diagnosis difficult. A probable allergic origin is being suggested because of the typical eosinophil-rich inflammatory reaction. Finally the diagnosis of Eosinophilic Angiocentric Fibrosis was given. It is a diagnosis of exclusion having characteristic histomorphological findings thus biopsy is always required to distinguish it from other lesions whose treatment differs.